Coil separator

ABSTRACT

A coil spacer adapted to be interposed between a pair of stacked coils in an annealing furnace. The spacer has two superimposed contiguous layers of wedge shaped plates arranged to define an annulus with a central opening. In one form the plates of one layer are radially extending defining radially extending channels and the plates of the other layer are skewed with respect to the radius to defining skewed channels intersecting the channels defined by the other layer. In another form the plates in each layer are skewed radially in opposite senses. In this form the plates are arranged so that their outer edges are rotatably offset to form a continuous outer surface and preferably the inner ends also are offset to form a continuous inner peripheral surface.

United States Patent [191 Blackman Jan. 1, 1974 COIL SEPARATOR [22] Filed: Mar. 16, 1972 [21] Appl. No.: 235,128

Primary Examinerlohn J. Camby Att0rneyWilliam N. Hogg 5 7] ABSTRACT A coil spacer adapted to be interposed between a pair of stacked coils in an annealing furnace. The spacer has two superimposed contiguous layers of wedge shaped plates arranged to define an annulus with a central opening. In one form the plates of one layer are radially extending defining radially extending channels and the plates of the other layer are skewed with respect to the radius to defining skewed channels intersecting the channels defined by the other layer. In another form the plates in each layer are skewed radially in opposite senses. In this form the plates are arranged so that their outer edges are rotatably offset to form a continuous outer surface and preferably the inner ends also are offset to form a continuous inner peripheral surface.

10 Claims, 7 Drawing Figures COIL SEPARATOR BACKGROUND OF THE INVENTION This invention relates generally to so called convector plates, and more particularly to convector or coil separator plates which are spacer members adapted to be used between coils of strip steel which are stacked vertically in a bell type annealing furnace for heat treating purposes.

For certain heat treating purposes it is customary to stack the coils of steel on edge with their eyes in vertical alignment and then enclose the stacked coils with an inner cover. A furnace or outer cover is placed over the inner cover or a group of inner covers to supply the heat.

It is desirable to obtain maximum circulation of the gases within the inner covers around the coils to afford maximum rate of heat transfer and for certain types of metallurgical processes. To this end it has become common practice to provide annular convector or separator plates between each of the coils in the stack, which plates are of various design providing different shaped channels for directing gases into contact with the edges of the coils both above and below the plates. To enhance the flow of gas it is conventional practice to provide a fan which causes circulation of the gases through the aligned inner eyes of the coils and around the outer edges, the gas flowing radially through the passages provided by the convector plates. These convector or space plates have taken many forms in the past, the modern trend being to a form of wedge plate construction, in which two layers of generally wedge shaped plates are provided in superimposed relationship. Examples of such wedge plate construction are shown in US. Pat. Nos. 3,415,506, 3,423,079 and 3,618,921. The construction of these plates in many ways is superior to the prior art design in that they allow wide passages for gas flow and provide solid support areas for the coils. However, these constructions have several drawbacks.

Basically, in all of these constructions the two layers of superimposed plates are each skewed at an angle with respect to a true radius. This creates channels radiating from the center in both a clockwise sense and counterclockwise sense from a true radius. This is an inefficient design for producing maximum radial gas flow outlet at the ID of the plate.

This inefficiency results from the fact that high convention fans create a vortex circular flow down the inside of a coil stack and a radial one directional rotation is best to maintain high circulation of the fan system. In other words, the passages being set at opposite senses, and hence one set counter to the radial direction, work at cross purposes with each other and are not the best for maintaining high circulation of the fan system.

Another drawback to the skewed construction is that the surface direction of radial expansion and contraction of the coils is radially outwardly and inwardly while the direction of expansion and contraction of the plates is in a direction skewed with respect to the radius which thus results in a differential expansion between the coils and plates. This contributes to the mechanical failure of the plates such as by swedging of sections, rolling over of the bars, etc.

Also, these prior art designs have provided a construction where the outer peripheries and the inner peripheries of the plates of each of the two sections are substantially coextensive with each other thus providing gaps or a discontinuous outer periphery and inner periphery. These spaces or gaps in the outer periphery tend to catch on various objects around such as the corrogated covers and other structures thus potentially causing damage. Also, the inner peripheries do not afford satisfactory gripping surfaces for certain types of lifting devices due to the discontinuities and noncontinuousnature of the peripheries.

SUMMARY OF THE INVENTION According to the present invention, a wedge plate type convector plate is provided having two contiguous layers of fiat metal plate in superimposed contact connected relationship, the plates being arranged and configured to define a central opening. In one embodiment the plates in one layer are outwardly tapered and extend substantially radially from the central opening and the plates in the other layer are likewise outwardly ta pered but are skewed in one direction with respect to the radii of the plate. The plates may also be arranged to provide a continuous inner and/or outer periphery surface between the upper and lower plates. In another embodiment the plates in each layer are skewed but provide a continuous inner and/or outer periphery surface.

DESCRIPTION OF THE DRAWING FIG. 1 is a plan view of one embodiment of the convector plate according to this invention;

FIG. 2 is a sectional view taken substantially along the plane designated by the line 2-2 of FIG. 1;

FIG. 3 is a sectional view taken substantially along the arcuate plane designated by the line 3-3 of FIG.

FIGS. 4 through 7 are partial plan views of other embodiments of convector plates according to this invention.

DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring now to the drawing, and for the present to FIGS. 1 through 3, one embodiment of a convector plate according to this invention is shown. First and second layers of plate members 10 and 12 are provided in superimposed contacting connected relationship. Theplates are preferably connected together by welds 14 along their edges as shown in FIGS. 2 and 3 and define a generally annular structure. Each of the plates 10 is of generally wedge shape being outwardly tapered plates. The set of plates 12 are also generally wedge shape and tapered outwardly. These plates however are skewed or angled with respect to the radius R of the annulus. The plates 12 are also separated and define between adjacent plates channels 18. Of course the channels l6 and 18 intersect each other which will cause a turbulence and mixing of the gases which are moving through these channels.

The layers of plates 10 and 12; together define an inner periphery designated by the reference character 20 (which bounds a central opening 21) and an outer periphery designated by a reference character 22. As can be seen in this embodiment, plates and 12 at the inner periphery are in substantial alignment with each other, whereas at the outer periphery 22 the plates are somewhat offset with each other although they do not define a continuous outer periphery. The inner periphery too, as can be seen, is not continuous. The angle and shape of the plates 12 is such that each plate at the inner periphery contacts the next adjacent plate to the one it contacts at the outer periphery; ie the plates 10 and 12 are each in contact with only two plates of the other layer. For ease of visualization of this the contacting area of three of the plates 12 with the plates 10 is shown with a crosshatch symbol.

As can be seen from FIG. 1, the sets of channels 16 extend radially and the channels 18 are skewed so that there is not a counter or cross purpose such as would occur if the channel 16 were skewed in the opposite sentence with respect to the channels 18. Rather there is one set of channels 18 which will impart a swirling motion and the other set of channels 16 is normal thereto which will not counteract or act in a countervailing manner to oppose this directional movement. Thus efficient utilization of gas circulation by the fan is provided. Also, the passages 16 and 18 do intersect to provide the desired turbulence to the gases as they are moving in the channels which, as is well known, provides a more efficient heat transfer to the edges of the coil.

Also it will be observed that the plates 10 extend radially and the plates 12 are only slightly skewed so that substantial portion of the expansion is generally radial which corresponds to the expansion of the coils in contact therewith. This will tend to overcome buckling and bowing of edges which can and does occur on convector plates due to the differential expansion between the plates of the convector and the coils in contact therewith.

As can be seen in FIG. 1 and as mentioned above there is not a continuous inner and outer periphery provided; i.e. there are gaps where the plates of the two layers do not completely overlap. As pointed out above, one of the drawbacks to prior art design was these gaps and the embodiment shown in FIG. 4 maintains all the advantages of FIG. 1 and further provides a continuous inner and outer periphery. In this embodiment radially extending plates 10a and skewed plates 12a are provided, wherein the plates 12a have somewhat wider outer edges so that at their outer edges the plates 12a extend completely across the channels 16a between the plates 10a so as to provide a complete continuous peripheral surface. At the inner periphery the plates 12a also are not coextensive with the inner edges of the plates 10a but actually are offset with respect thereto and extend therebetween. Thus also a continous inner periphery 20a is provided as well as the continuous outer periphery 22a. It will be noted, however, that the passages 16a and 18a are not quite as wide as those in the embodiment of FIG. 1 so that there is a certain sacrifice in passage width thereby diminishing the amount of gas flow and the contact area of the gas between the edges of the coils. This can be increased somewhat by slightly modifying FIG. 4 so that the plates 12a extend just to the next adjacent plate without a substantial overlap in the area shown crosshatch.

Referring now to FIG. 5 yet another embodiment of this invention is shown. In this embodiment there is a layer of radially extending plates 10b in contacting connecting relationship with a layer of skewed plates 12b. In this embodiment, however, the plates 12b are curved or of an arcuate configuration so that the curved edges form arcuate channels 18b while the channels 16b are straight as in the previously discussed embodiment. In this embodiment as in the embodiment of FIG. 4 the plates are arranged so as to form a continuous inner periphery 20b and continuous outer periphery 22b.

In order to provide larger channels but at the sacrifice of continuous inner and outer peripheries the embodiment shown in FIG. 6 can be utilized wherein again there is straight edged radial plates 10c and skewed arcuate plates 120. However, in this embodiment the arcuate plates have their inner and outer edges substantially contiguous with the inner and outer edges of the straight plates so that there is a discontinuous inner and outer periphery. This, however, provides wider channels 16 and for the gases and thus more contact area for the coils supported on the plate.

Referring now to FIG. 7, still another embodiment of this invention is shown wherein a continuous inner and outer periphery is provided in a wedge plate type construction. However, in this construction oppositely skewed plates are provided and this construction is useful where minimal consideration need be given to the flow pattern of the gases and differential expansion but where the prime consideration is a complete inner and outer periphery. In this embodiment a layer of plates 30 is provided which plates are similar in construction to the plates 12 of FIG. 1 and skewed in the same sense. Another layer of plates 32 is also provided in superimposed contacting relationship which plates are similar in shape and size to the plates 30 but are skewed in the opposite direction, their being a mirror image of the plates 30. These plates 30 and 32 are each shaped and arranged so that they overlap the outer edges and inner edges of the opposite layer of plates to such an extent that a continuous outer periphery 34 and continuous inner periphery 36 is provided with gas passages 38 and 40 defined between the plates 30 of the upper layer and 32 of the lower layer respectively. The overlapped area of three of the plates 30 with the plates 32 is shown in crosshatch in this embodiment.

What is claimed is: l. A coil spacer adapted to be interposed between a pair of coils in an annealing furnace comprising,

two contiguous layers of flat metal plates in superimposed contacting connected face-to-face relationship, the plates being arranged and configured to define generally an annulus with a central opening, the plates in one layer being individually outwardly tapered and extending substantially radially from said central opening and defining passages extending radially therebetween; the plates in the other layer being individually outwardly tapered and skewed in one direction with respect to the radii of the armature and defining passages extending skewed radially therebetween. 2. The invention as defined in claim 1 wherein the outer edges of the plates of the two layers are circumferentially offset with respect to each other.

3. The invention as defined in claim 2 wherein the outer edges of the plates define a substantially continuous outer peripheral surface.

4. The invention as defined in claim 2 wherein the inner edge of the plates define a substantially continuous inner peripheral surface.

5. The invention as defined in claim 2 wherein the outer and inner surfaces define substantial continuous outer and inner peripheral surfaces respectively.

6. The invention as defined in claim 1 wherein the edges of the plates of both layers are substantially straight.

7. The invention as defined in claim 1 wherein the plates of said other layer are of a curved configuration.

8. The invention as defined in claim 1 wherein each plate of one layer is contiguous with no more than two plates of the other layer.

9. A coil spacer adapted to be interposed between a pair of coils in an annealing furnace comprising,

two contiguous layers of flat metal plates insuperimposed contacting connected relationship, the plates being arranged and configured to define a central opening,

the plates in one layer being outwardly tapered and being skewed in one direction with respect to the radii of the spacer, defining passages extending skewed radially therebetween,

the plates in the other layer being outwardly tapered and being skewed in the opposite direction from those in said one layer with respect to the radii of the spacer and defining passages extending skewed radially therebetween,

the outer edges of the plates of the first and second layers being circumferentially offset with respect to each other and being of sufficient arc length that the ends of the plates of each layer form a substantially continuous outer surface.

10. The invention as defined in claim 9 wherein the inner edges of the plates of each layer are circumferentially offset with respect to each other and of being sufficient arc length that they define a substantially continuous innerperipheral surface.

UNITED STATES PATENT OFFICE I CERTIFICATE OF CORRECTION Dated 1,

Patent No. 894

Inventor(s) Calvin C, Blac kmann It is certified that error appears in the above-identified patent and that said Letters Patent are hereby corrected as shown below:

Column 2, line 15, "plate" should read --plates--,

Column 3, line '19, "sentence" should read --sehse--,

Column 4, line 60, "armature" should read --spacer.--,

Signed a nd sealed this 16th day of July 1974.

(SEAL) Attest:

MCCOY M. GIBSON, J Attesting Officer C. MARSHALL DANN Commissioner of Patents orm o-1o5o (10-69) uscoMM-Dc 60376-P69 fl' U,5. GOVERNMENT PRINTING OFFICE l9, 0-355-334 

1. A coil spacer adapted to be interposed between a pair of coils in an annealing furnace comprising, two contiguous layers of flat metal plates in superimposed contacting connected face-to-face relationship, the plates being arranged and configured to define generally an annulus with a central opening, the plates in one layer being individually outwardly tapered and extending substantially radially from said central opening and defining passages extending radially therebetween; the plates in the other layer being individually outwardly tapered and skewed in one direction with respect to the radii of the armature and defining passages extending skewed radially therebetween.
 2. The invention as defined in claim 1 wherein the outer edges of the plates of the two layers are circumferentially offset with respect to each other.
 3. The invention as defined in claim 2 wherein the outer edges of the plates define a substantially continuous outer peripheral surface.
 4. The invention as defined in claim 2 wherein the inner edge of the plates define a substantially continuous inner peripheral surface.
 5. The invention as defined in claim 2 wherein the outer and inner surfaces define substantial continuous outer and inner peripheral surfaces respectively.
 6. The invention as defined in claim 1 wherein the edges of the plates of both layers are substantially straight.
 7. The invention as defined in claim 1 wherein the plates of said other layer are of a curved configuration.
 8. The invention as defined in claim 1 wherein each plate of one layer is contiguous with no more than two plates of the other layer.
 9. A coil spacer adapted to be interposed between a pair of coils in an annealing furnace comprising, two contiguous layers of flat metal plates in superimposed contacting connected relationship, the plates being arranged and configured to define a central opening, the plates in one layer being outwardly tapered and being skewed in one direction with respect to the radii of the spacer, defining passages extending skewed radially therebetween, the plates in the other layer being outwardly tapered and being skewed in the opposite direction from those in said one layer with respect to tHe radii of the spacer and defining passages extending skewed radially therebetween, the outer edges of the plates of the first and second layers being circumferentially offset with respect to each other and being of sufficient arc length that the ends of the plates of each layer form a substantially continuous outer surface.
 10. The invention as defined in claim 9 wherein the inner edges of the plates of each layer are circumferentially offset with respect to each other and of being sufficient arc length that they define a substantially continuous innerperipheral surface. 